Auxiliary ram for stokers



ou. 1s, 192s. n 1,687,614

' D. C. HESS v AUXILIARY RAM FOR STOKERS Filed July s. 1922 2 sheets-sheet 1 /f// //V/ /I// 'DLHQJJ INVENTOR BY 9 l ATTORNEY ou, 16, 192s. Y 1,687,614

D. C. HESS AUXILIARY RAM FOR STOKERS Filed July 5. 1922 2 Sheets-Sheet 2 lNvEN wrrNEssEs:

Patented Oct. 16, 1928.

DUNCAN C. HESS, OFCHESTER, PENNSYLVANIA, .ASSIGNOR TO WESTINGHOUSE. ELEC- TRIUAND MANUFACTURING. COMPANY, A CORPQRAIION. OF PENNSYLVANIA.

j AUXILIARY'RAM FOR- STQKERS. Y

Application iled- July 5, 1922.. Serial No. 572,903.

The invention relates to` mechanical Stoker-s of the underfeed-type, and ithas as anobject to provide an auxiliary ram for stokers of the character designated which shall' effect a more complete combustion of that portion ofthe fuel bedwhichy passes from the rear ends of the retorts to the refusef grates. It has -fory a further object to maintain at a lrelativelyl low temperature those portions of the auxiliary ram which become under certain conditions' 'ofr opertioln exposed to the heat of the burning These andfotherobjects areefl'ected by my invention, as will be app/arentV from` the fol-lowinggdescription'-and claims taken inconnecti'onwith the accompanying drawings, form-inga; part'ofthis application, in which:y

1 is a fragmentary view in longitudinal section of anfoverfeed stokerembo'dying my invention;

Fig. 2 is a viewA invrear elevation of thtI auxiliary rainy Fig. B--isan'enlarged viewfin longitudinal section ofthe auxiliary ram; and,

Fig. llis the fragmentary plan viewof the stoker illustrated in Fig. 1, the ram being removed from` theI retort1 at: the right to show the openings therein. Y

' In the operation of stokers at the overload capacities employed'V in. central power stations, it has been found that the portions of the residue passing outk through the retorts contain a higher. percentage ofunconsumedl fuel than `the portions discharged from the twyer sections, and that, whenrthe fuel -is'fedto the furnace in such manner: as

to secure substantially complete.' combustion of this fuel `dischar `ged from the reto-rts, :the auxiliary rams `are `heated to such; a;V high: temperature asftocause them to burn out after relatively short periods of service.

The purpose of the present invention is to remedy these deficiencies by providing means for securing at overload capacities reasonably complete combustion kof the fuel discharged from the retorts and to'protect the auxiliary rams from destructively high temperatures under all operating conditions. This is accomplished by constructing Vthe auxiliary rams with a plurality of hollow pushing members `and causing air under pressure to pass through thehollow members into the fuel in the retorts. The conl form theside walls ofretorts struction serves a. two-fold purpose; it facilitates combustion in'zyones having a con. siderable unconsumed fuel content f and;y it cools themetallic portions of the ram, whichL are exposed to heat, sufficiently to `prenfentfa burningout of these members.

Referring-Ito .the drawing, I'show 'in Fig. 1 an underfeedV stoker of a conventional type, composedy of alternately. arranged retorts and twyer sections..` The` stoker retorts and twyers may bel of any ofthe well known underfeed stoken constructions,f` the present invention .beingin no wisel limited to the specilic structure of the underfeed stoker. Asy illustrated, the stokerpcom'prises twyer boxes 11, supported upon; suitable frame 'work 12, and lcarrying ftwyer me1n. bers 13.2 The twyerboxesfll areaspaced; to 14, which, as shown, include bottom: l plates members 416 and a coalv plate 17. ls-illus4 trated, the retorts .14 arev ofdecreasing.` depth from the; frontto the rear of theffurnace. A hopper 18 nis providedfat the front ofthe furnace. from whichV the fuel is. fed through the passage 19: by means of the lusual .recip-f rocating ram (not shown). Overfeed sections 21 are .providedy at therearxof the stoker, which may1 befof any well yknown* constructioinx in the present drawing, an oscillating section being illustrated; Air under pressureisffed to the chamber 22 beneath-the retorts and twyer boxes .in the usual tmanner, as througha conduit 23k pro-r vided with avalve y2st. 5

Ari-.auxiliary ram 30wis disposed in each retort andis adaptedy to befreciprocated therein by: ineansoffa. rod 31 connected to the driving `mechanism i of the,y stokery (not shown). "As illustratedlinFig. 3, theram comprises a baseplate 82wto;which is attached adependinglug .33 connected to thefrodl I for transmitting reciprocatory motion to the ram. kA plurality of demountable pusher members, 36 and 37 of Abox-like construction and carried by the base plate 32 and form therewith the hollow pusher members 35, 36 andBT areprovided with air ports, 38, 39 and 40 respectively. The ports are located in the upper portion of the rear facey of eachpusher `member and 'are preferably inclined downwardly to prevent the clogging thereof with fuel. y

vThe auxiliary ram 30 slides upon` the bottom plate 15 of the retort,`a slot 4:2 being' 15, deflector ram 30; The

los

plurality of spaced ports 46, 47 and 48which are adapted to register with ports 43, 44 and 45 respectively, thereby providing. a means p' for admitting air at all times to the interior portions of the pushers 35, 36 and 37 respectively. It will beobserved that the ports 46 in the rearward pusher member 35, are larger in area than the. ports 47 in the intermediate pusher member 36, and that ports 47 are larger in area'than the ports :4S in the forward pusher member 3T. The purpose of the different size ports is to supply air for combustion in increasing amounts from the front to the rear of the stoker for the reasonV that more air for cooling the pusher mem bers and for supporting combustion is required wherethe. greatest amount of active combustion is present. y

The operation of the above vdescribed structure is as follows: The fuel is forced into the retort through the passage 19 and elevated to cover the twyers 13 by means vof the deflector plate 16. The auxiliary ram 30 is reciprocated to agitate and break up the partially coked fuel as it approaches the rear of the stoker and to push rearwardly the residue of the fuel onto the overfeed grates 2l. Inr this operation, the nose of the pusher membersv may be subjected to the heat of the furnace and of the burning Yrefuse in such manner as to cause a rapid deterioration of hese elements. To effect a cooling of these elements, air Linder pressure is admitted into the interior of the ram 30 from the chamber 22 through the registering openings V43, 46, 44, 47 and 45, 48 and dischargedthrough ports 38, 39, 40 into the burning fuel where it assists in the combustion of the un consumed portions of the refuse being Vdelivered to the overfeed` grates 21. A cooling of the auxiliary pusher and a morecomplete combustion of fuel consequently results.

While I have shown my invention in sev-l eral forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modiiications without departing from the spirit thereof, and I desire, therefore, that only such are specifically set claims.L

` l/Vliat I claim is: v n g l. In combination in an underfee'd stoker, a fuel feeding retort, an auxiliary ram in the retort, said auxiliary rain comprising a plurality kofliellow, step-like pusher members, each of said pusher members having a port disposed to deliver air into'the fuel bed, said retort and said pusher members forth in the appended each being provided with a series ,ofopen-- ings, the openings ofsaid retort registering with the openings of said pusher member, the openingsof at least one series being of graduated size. n 2. In an underfeed Stoker, an airy box, la fuel feeding retort vextending rearwardly from the front ofthe Stoker and provided with a plurality of openings in its bottom communicatin g with the air box, rain structure in the retort comprising a plurality of 'box-like pushermembers adapted to slide on the retort bottom, each of said Vmembers lbeing provided with air opening direction of fuelfeed and with openingsvreg# an auxiliary l Us for -dischardinffair vintolthe fuel in the imitations Shan be; piaceri there upon as are imposed by the prior art or as istering` with the openings in the retort b ot- 3. In an underfeed Stoker, an air box, a

tlie'openings registering with the open fuel feeding retort extending rearwardlyk from the Ifront ofthe stoker and provided with a plurality of openings in its bottom communicating with the air box, an auxiliary ram structure in the retortA comprising a plurality of box-like pusher members adapted to slide on the retort, bottom, each of said members being provided ywith air openingsifor discharging'air into the' fuel in the direction offuel feed and with openings registering'with the openings iny the retort bottom, isteringiwith the openings in the retort` bottom progressively increasing in area from front to rear. f H

In testimony whereof, I have hereunto subscribed 'mynam'e this 29th day of June, 1922.

DUNCAN CfHESS,

the openings in the pusher members regr 

